That looks like the regulator hole, not sure if the m3 and m2 are different but. If tightening the grub screw as suggested doesn't fix ut then you need to replace the o ring on the regulator housing.
Well, I've spent about 4 hours looking up i fo on optics to put on my new gk1 .22 that should be coming in on Tuesday, I bought a LPVO, a 4x prism, dovetail to picatiny mounts, scope rings, GK1 mounts, and a variety of ammo to try in the new pistol.
I did use to own a kalibrgun cricket 2 45 and I loved it aside from the annoying magazine loading design although better than the original cricket. And the ping, the ping got to me. I've heard it's not bad on the 60 due to the longer barrel but I could not tell you. Mine did shoot pellets...
Iguanas lol. I was hunting iguanas in my community with a sling bow (sling shot and bow hybrid). Then I see I guy walking around looking for iguanas and I pointed out to him where I've been seeing them. He asked me what I was doing with my weird contraption, I told him I was hunting iguanas so...